THE PRESENT INVENTION relates to a coupling for connecting railing members to a post such that the posts and railing members may adopt any configuration and adapt to any terrain. In particular, although not exclusively, the present invention relates to a coupling for constructing a fence which readily lends itself to connecting prefabricated fencing components.
The coupling will be described by way of example with reference to its use in constructing a fence. It should be appreciated that this is by way of example only and that the coupling may be used to construct barriers, signs, partitions or the like.
Fence couplings which allow a fence railing to pivot with respect to the fence post about both a horizontal and a vertical axis are known. U.S. Pat. No. 3,960,367 discloses brackets in the form of collars which encircle posts and are pivotally connected to rails and can be adjusted on the posts both vertically and rotationally. The disadvantage of such brackets is that the collars are only maintained in position on the posts by virtue of friction and following assembly, the collars may become misaligned especially if a heavy blow is applied to the fence railing. In assembling a fence using the collar of the above patent, it is necessary to conduct measurements to determine the desired location of the collars along the posts. A further disadvantage of this bracket is that the ends of the fence railing are left exposed and as a result the construction is not aesthetically pleasing.
Australian Patent Application No. 20168/83 discloses a fence coupling comprising a fitting clasped around a vertical fence post and located by means of a fastener. A socket is formed in the fitting and a ball member is receivable therein. The ball member is connectable to a fence railing. This arrangement has similar disadvantages to the abovementioned United States patent in that a heavy blow to the fence railing may cause misalignment of the fence railing between adjacent posts or may even cause the ball to pop out of the socket. A further disadvantage is that measurements must be made on assembly to determine the location of the fitting on the fence post. This does not easily lend itself to simple assembly of prefabricated fencing components.
Australian Patent Application No. 59162/90 discloses a similar ball and socket fence coupling. However, in this case, the ball member is attached to a plate affixed to the fence post by fasteners and the socket member is connected to the railing member. As with other prior art, this fence coupling requires measurements to be made during assembly of the fence. A major disadvantage of this construction is that pivotal motion in a horizontal plane to allow a fence constructed using the coupling to adopt any configuration, occurs about a vertical axis which is spaced from the centre of the post. This feature may give rise to some difficult geometric problems when designing the fence.
U.S. Pat. No. 3,410,527 discloses a fence coupling comprising a semi-circular snap ring, the ends being rotatably mounted in bearing holes in the fence post. These snap rings may be held at any angle within an arc of 110.degree. taken from the centre of the bearing holes. The snap rings are loosely retained in a rectangular opening of a terminal cap which is connected to the fence railing. The loose retention of the snap ring permits positioning of the fence rail within a horizontal arc of 190.degree.. Again, the pivotal motion of the railing in a horizontal direction is not centred at the centre of the post and therefore difficult geometric problems may also arise in designing a fence using the disclosed fence coupling. Further, the fact that the terminal caps are loosely retained on the snap rings could result in a fence of weak construction.